Few clinicians are familiar with the anatomy of anomalous pulmonary veins, and studies reporting patients who required right lower lobectomy for lung cancer and who had anomalies of the middle and lower pulmonary veins are even rarer. This report describes the case of a lung cancer patient who had an anomalous lateral part of the middle lobe vein (V4) draining into the right inferior pulmonary vein, which was confirmed by three-dimensional 64-row multidetector computed axial tomography (3D-MDCT) angiography. She was then successfully treated with video-assisted thoracic surgery. The preoperative 3D imaging of the pulmonary vein and artery allowed us to comprehend fully the patient's vascular anatomy before the operation. Thus, we recommend preoperative 3D-MDCT angiography for patients with lung cancer undergoing thoracic surgery, especially video-assisted thoracic surgery.